HPLC Quantification of rDNA Polypeptides Like Insulin Precursors Produced in Yeast

A reversed-phase HPLC system for the quantification of recombinant DNA insulin precursors in yeast fermentation broth is described. HPLC monitoring of the polypeptide can be achieved without interference from substrate components or proteins stemming from the host cell, thus serving to determine the optimum harvesting time. Furthermore, it is demonstrated how different amino acid links of the insulin A- and B-chains affect the chromatographic behaviour of the insulin precursor making it possible to identify each precursor by its retention on the reversed phase support.